TWI767019B - Liquid crystal alignment agent, liquid crystal alignment film and liquid crystal display element - Google Patents

Abstract

The invention relates to a liquid crystal alignment including: a polymer (A) which is formed by reaction of a mixture including a tetracarboxylic dianhydride component (a) and a diamine component (a2); and a solvent (b) including a compound (B-1) represented as formula (1), 4,6-Dimethyl-2-heptanone (B-2) and 2,6-Dimethyl-4-heptanone (B-3). The liquid crystal alignment agent of the invention has the advantages of favorable coating properties for inkjet printing. The invention further relates to a liquid crystal alignment film formed of the liquid crystal alignment agent, and a liquid crystal display element including the liquid crystal alignment film.

Description

Liquid crystal alignment agent, liquid crystal alignment film and liquid crystal display element

The present invention relates to a liquid crystal alignment agent and a method for producing the same, a liquid crystal alignment film and a method for producing the same, and a liquid crystal display element, in particular to a liquid crystal alignment agent with good inkjet printing coating properties and a method for producing the same, and the liquid crystal alignment agent described above. The formed liquid crystal alignment film, its manufacturing method, and the liquid crystal display element provided with the said liquid crystal alignment film.

As consumers' requirements for the wide viewing angle characteristics of liquid crystal displays are increasing year by year, the requirements for the electrical characteristics or display characteristics of liquid crystal display elements with wide viewing angles are more stringent than before. Display elements are the most widely studied. In order to have the above-mentioned characteristics better, the liquid crystal alignment film has become one of the important research objects to improve the characteristics of the vertical alignment type liquid crystal display element.

The liquid crystal alignment film in the vertical alignment type liquid crystal display element is mainly used to arrange the liquid crystal molecules regularly and to make the liquid crystal molecules have a large inclination angle without an electric field, and the formation method of the liquid crystal alignment film is usually A liquid crystal alignment agent containing polymer materials such as polyimide polymer and polyimide polymer is coated on the surface of a substrate, and is formed after heat treatment and alignment treatment.

The liquid crystal alignment agent is usually a liquid composition prepared by dissolving polymer components in a solvent, and the liquid composition is then coated on a substrate and heated to form a liquid crystal alignment film. The solvent selected for the liquid crystal alignment agent must be able to dissolve the polymer uniformly, and aprotic polar solvents such as N-methyl-2-pyrrolidone or γ-butyrolactone are usually used. In addition, in order to make the coating property (printability) of the liquid crystal aligning agent good when it is applied to the substrate, an organic solvent with low surface tension such as butyl cellosolve can be used in combination with an aprotic polar solvent (such as Japanese Laid-Open Patent Publication No. 2010-97188 and Japanese Patent Laid-Open No. 2010-156934).

In recent years, LCD TVs have gradually become popular, and production lines have gradually become larger. The advantage of using a large production line to increase the size of the substrate is that a plurality of panels can be formed from one substrate, so the processing time and cost can be shortened, and the size of the liquid crystal display element itself can be increased. On the other hand, the disadvantage of an enlarged substrate is that it is difficult to ensure the uniformity of the large-area printing of the liquid crystal aligning agent. In particular, when a large-area film is formed by a widely used offset printing machine, it is easy to cause electrical defects in the liquid crystal alignment film due to poor printing of the liquid crystal alignment agent.

In order to overcome the above-mentioned problems, the industry uses an inkjet coating method to form a liquid crystal alignment film. The advantage of the inkjet coating method is that the amount of liquid crystal alignment agent used in printing is approximately the same as the liquid amount actually applied, so it is expected that the amount of liquid crystal alignment agent used can be reduced. In addition, the time, labor, and cost required for maintenance (replacing and cleaning the printing plate) can be reduced because the printing plate does not need to be used, and the flexibility can be used to handle panels of various sizes.

Therefore, there is an urgent need to provide a liquid crystal alignment agent, which has the advantages of good inkjet printing coating properties, and can be used in, for example, inkjet coating methods, so that the formed liquid crystal alignment film can have better performance when applied to liquid crystal display elements. Display quality.

The present invention obtains a liquid crystal aligning agent by providing a special polymer and a solvent, and the liquid crystal aligning agent has the advantage of good ink-jet printing coatability.

式(1) 式(1)中，R₁ 為C₂ 至C₁₂ 之烷基。Therefore, the present invention provides a liquid crystal alignment agent, comprising: a polymer (A) prepared by reacting a mixture comprising a tetracarboxylic dianhydride component (a) and a diamine component (b); and a solvent (B) ), including compound (B-1), 4,6-dimethyl-2-heptanone (B-2) and 2,6-dimethyl-4-heptanone (B- 3);

Formula (1) In formula (1), R ₁ is a C ₂ to C ₁₂ alkyl group.

The present invention further provides a liquid crystal alignment film, which is formed by the aforementioned liquid crystal alignment agent.

The present invention further provides a liquid crystal display element comprising the aforementioned liquid crystal alignment film.

The present invention further provides a method for manufacturing a liquid crystal alignment film, which is to form a liquid crystal alignment film from the aforementioned liquid crystal alignment agent by an inkjet printing method.

式(1) 式(1)中，R₁ 為C₂ 至C₁₂ 之烷基。The present invention provides a liquid crystal alignment agent, comprising: a polymer (A) prepared by reacting a mixture comprising a tetracarboxylic dianhydride component (a) and a diamine component (a); and a solvent (B), Including compound (B-1) represented by formula (1), 4,6-dimethyl-2-heptanone (B-2) and 2,6-dimethyl-4-heptanone (B-3) ;

Formula (1) In formula (1), R ₁ is a C ₂ to C ₁₂ alkyl group.

The present invention further provides a liquid crystal alignment film, which is formed by the aforementioned liquid crystal alignment agent.

The polymer (A) of the present invention is prepared by reacting a mixture comprising the tetracarboxylic dianhydride component (a) and the diamine component (b). Specifically, the polymer (A) can be selected from a polyimide polymer, a polyimide polymer, a polyimide-based block copolymer, or any combination of the aforementioned polymers. Wherein, the polyimide block copolymer is selected from the group consisting of polyimide block copolymer, polyimide block copolymer, polyimide-polyimide block copolymer or Any combination of the above polymers.

The tetracarboxylic dianhydride component (a) includes aliphatic tetracarboxylic dianhydride compounds, alicyclic tetracarboxylic dianhydride compounds, aromatic tetracarboxylic dianhydride compounds, from formula (a-1) to formula ( At least one of the tetracarboxylic dianhydride compounds represented by a-6), or a combination of the above compounds.

Specific examples of the aliphatic tetracarboxylic dianhydride compound may include, but are not limited to, ethane tetracarboxylic dianhydride, butane tetracarboxylic dianhydride, or a combination of the above compounds.

Specific examples of the alicyclic tetracarboxylic dianhydride compound may include, but are not limited to, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2-dimethyl-1,2,3,4 -Cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dichloro-1,2,3,4- Cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetra Carboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3',4,4'-dicyclohexyltetracarboxylic dianhydride, cis-3,7-dibutyl cycloheptyl-1,5-diene-1,2,5,6-tetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, bicyclo[2.2.2]-octane -7-ene-2,3,5,6-tetracarboxylic dianhydride or a combination of the above.

Specific examples of the aromatic tetracarboxylic dianhydride compound may include, but are not limited to, 3,4-dicarboxy-1,2,3,4-tetrahydronaphthalene-1-succinic dianhydride, pyromellitic dianhydride , 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 1,4,5,8-naphthalene tetra Carboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 3,3'-4,4'-diphenylethane tetracarboxylic dianhydride, 3,3',4,4' -Dimethyldiphenylsilane tetracarboxylic dianhydride, 3,3',4,4'-tetraphenylsilane tetracarboxylic dianhydride, 1,2,3,4-furan tetracarboxylic dianhydride, 4 ,4'-bis(3,4-dicarboxyphenoxy)diphenyl sulfide dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenylene dianhydride, 4,4' -Bis(3,4-dicarboxyphenoxy)diphenylpropane dianhydride (4,4'-bis(3,4-dicarboxy phenoxy)diphenylpropane dianhydride), 3,3',4,4'-perfluoroiso Propylene diphthalic dianhydride, 3,3',4,4'-diphenyltetracarboxylic dianhydride, bis(phthalic acid) phenylphosphine oxide dianhydride, p-phenylene-bis( Triphenylphthalic acid) dianhydride, m-phenylene-bis (triphenylphthalic acid) dianhydride, bis (triphenylphthalic acid)-4,4'-diphenyl ether dianhydride, Bis(triphenylphthalic acid)-4,4'-diphenylmethane dianhydride, ethylene glycol-bis(anhydrotrimellitate), propylene glycol-bis(anhydrotrimellitate), 1, 4-Butanediol-bis(anhydrotrimellitate), 1,6-hexanediol-bis(anhydrotrimellitate), 1,8-octanediol-bis(anhydrotrimellitate) ), 2,2-bis(4-hydroxyphenyl)propane-bis(anhydrotrimellitate), 2,3,4,5-tetrahydrofuran tetracarboxylic dianhydride, 1,3,3a,4,5 ,9b-Hexahydro-5-(tetrahydro-2,5-dioxy-3-furyl)-naphtho[1,2-c]-furan-1,3-dione{(1,3 ,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)naphtho[1,2-c]furan-1,3-dione)}, 1,3,3a, 4,5,9b-Hexahydro-5-methyl-5-(tetrahydro-2,5-dioxy-3-furyl)-naphtho[1,2-c]-furan-1,3 -diketone, 1,3,3a,4,5,9b-hexahydro-5-ethyl-5-(tetrahydro-2,5-dioxy-3-furyl)-naphtho[1, 2-c]-Furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-7-methyl-5-(tetrahydro-2,5-dioxy-3 -furyl)-naphtho[1,2-c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-7-ethyl-5-(tetrahydro- 2,5-Di-oxy-3-furyl)-naphtho [1,2-c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2,5-dioxygen yl-3-furyl)-naphtho[1,2-c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-8-ethyl-5-( Tetrahydro-2,5-dioxy-3-furyl)-naphtho[1,2-c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexa Hydro-5,8-dimethyl-5-(tetrahydro-2,5-dioxy-3-furyl)-naphtho[1,2-c]-furan-1,3-dione, Aromatic tetracarboxylic dianhydride compounds such as 5-(2,5-di-oxytetrahydrofuranyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic acid dianhydride, or combinations thereof.

式(a-1)

式(a-2)

式(a-3)

式(a-4)

式(a-5) 式(a-5)中，A₁ 表示含有芳香環的二價基團；r表示1至2的整數；A₂ 及A₃ 可為相同或不同，且可各自獨立表示-H或烷基。由式(a-5)表示的四羧酸二酐化合物的具體例包括由式(a-5-1)至式(a-5-3)表示的化合物中的至少一種。

式(a-5-1)

式(a-5-2)

式(a-5-3)

式(a-6) 式(a-6)中，A₄ 表示含有芳香環的二價基團；A₅ 及A₆ 可為相同或不同，且各自獨立表示-H或烷基。由式(a-6)表示的四羧酸二酐化合物較佳為由式(a-6-1)表示的化合物。

式(a-6-1)The tetracarboxylic dianhydride compounds represented by formula (a-1) to formula (a-6) are shown below:

Formula (a-1)

Formula (a-2)

Formula (a-3)

Formula (a-4)

Formula (a-5) In formula (a-5), A ₁ represents a divalent group containing an aromatic ring; r represents an integer of 1 to 2; A ₂ and A ₃ may be the same or different, and may each independently represent -H or alkyl. Specific examples of the tetracarboxylic dianhydride compound represented by formula (a-5) include at least one of the compounds represented by formula (a-5-1) to formula (a-5-3).

Formula (a-5-1)

Formula (a-5-2)

Formula (a-5-3)

Formula (a-6) In formula (a-6), A ₄ represents a divalent group containing an aromatic ring; A ₅ and A ₆ may be the same or different, and each independently represents -H or an alkyl group. The tetracarboxylic dianhydride compound represented by formula (a-6) is preferably a compound represented by formula (a-6-1).

Formula (a-6-1)

Preferably, the tetracarboxylic dianhydride component (a) includes but is not limited to 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic acid di- Anhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,4-dicarboxy-1,2,3,4-tetra Hydronaphthalene-1-succinic dianhydride, pyromellitic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride and 3,3',4,4'-biphenyl Tetracarboxylic dianhydride. The tetracarboxylic dianhydride component (a) may be used alone or in combination of two or more.

The diamine component (b) includes an aliphatic diamine compound, an alicyclic diamine compound, an aromatic diamine compound, a diamine compound represented by formula (b-1) to formula (b-26), or its combination.

Specific examples of the aliphatic diamine compound include, but are not limited to, 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane Alkane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane Alkane, 4,4'-diaminoheptane, 1,3-diamino-2,2-dimethylpropane, 1,6-diamino-2,5-dimethylhexane, 1, 7-Diamino-2,5-dimethylheptane, 1,7-diamino-4,4-dimethylheptane, 1,7-diamino-3-methylheptane, 1 ,9-Diamino-5-methylnonane, 2,11-diaminododecane, 1,12-diaminooctadecane, 1,2-bis(3-aminopropoxy) Ethane, or a combination of the above.

Specific examples of the alicyclic diamine compound include, but are not limited to, 4,4'-diaminodicyclohexylmethane, 4,4'-diamino-3,3'-dimethyldicyclohexylamine, 1 ,3-diaminocyclohexane, 1,4-diaminocyclohexane, isophorone diamine, tetrahydrodicyclopentadiene diamine, tricyclo[6.2.1.02,7]-undecane Carbendimethyldiamine, 4,4'-methylenebis(cyclohexylamine), or a combination of the foregoing.

Specific examples of the aromatic diamine compound include, but are not limited to, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, 4,4'-diaminodiphenyl Base, 4,4'-diaminobenzylaniline, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 1,5-diaminonaphthalene , 5-amino-1-(4'-aminophenyl)-1,3,3-trimethylhydroindene, 6-amino-1-(4'-aminophenyl)-1,3 ,3-Trimethylhydroindene, Hexahydro-4,7-methylhydroindenyl dimethylenediamine, 3,3'-diaminobenzophenone, 3,4'-diamino Benzophenone, 4,4'-Diaminobenzophenone, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4 -Aminophenoxy)phenyl]hexafluoropropane, 2,2-bis(4-aminophenoxy)hexafluoropropane, 2,2-bis[4-(4-aminophenoxy)phenyl ] bismuth, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene , 9,9-bis(4-aminophenyl)-10-hydroanthracene, 9,10-bis(4-aminophenyl) anthracene [9,10-bis(4-aminophenyl) anthracene], 2, 7-Diamino fluoride, 9,9-bis(4-aminophenyl) fluoride, 4,4'-methylene-bis(2-chloroaniline), 4,4'-(p-phenylene Isopropylidene) bisaniline, 4,4'-(m-phenylene isopropylidene) bisaniline, 2,2'-bis[4-(4-amino-2-trifluoromethylphenoxy] base)phenyl]hexafluoropropane, 4,4'-bis[(4-amino-2-trifluoromethyl)phenoxy]-octafluorobiphenyl, 5-[4-(4-n-pentane cyclohexyl)cyclohexyl]phenyl-methylene-1,3-diaminobenzene{5-[4-(4-n-pentylcyclohexyl)cyclohexyl]phenylmethylene-1,3-diaminobenzene}, 1,1- Bis[4-(4-aminophenoxy)phenyl]-4-(4-ethylphenyl)cyclohexane{1,1-bis[4-(4-aminophenoxy)phenyl]-4-( 4-ethylphenyl)cyclohexane}, or a combination of the above.

式(b-1) 式(b-1)中，B¹ 表示

、

、

、

、

，或

； B表示具有甾(膽固醇(steroid))骨架的基、三氟甲基、氟基、碳數為2至30的烷基、或衍生自吡啶、嘧啶、三嗪、哌啶或哌嗪等含氮原子環狀結構的一價基團。The diamine compound represented by formula (b-1) is shown below:

Formula (b-1) In formula (b-1), B ¹ represents

,

,

,

,

,or

; B represents a group with a steroid (steroid) skeleton, a trifluoromethyl group, a fluoro group, an alkyl group with a carbon number of 2 to 30, or a group derived from pyridine, pyrimidine, triazine, piperidine or piperazine containing A monovalent group of a ring structure of nitrogen atoms.

Specific examples of the compound represented by formula (b-1) include, but are not limited to, 2,4-diaminophenyl ethyl formate, 3,5-diaminophenyl ethyl formate Ester (3,5-diaminophenyl ethyl formate), 2,4-diaminophenyl propyl formate (2,4-diaminophenyl propyl formate), 3,5-diaminophenyl propyl formate (3,5-diaminophenyl propyl formate) diaminophenyl propyl formate), 1-dodecoxy-2,4-diaminobenzene (1-dodecoxy-2,4-diaminobenzene), 1-hexadecoxy-2,4-diaminobenzene ( 1-hexadecoxy-2,4-diaminobenzene), 1-octadecoxy-2,4-diaminobenzene (1-octadecoxy-2,4-diaminobenzene), from formula (b-1-1) to formula At least one of the compounds represented by (b-1-6), or a combination of the above compounds.

式(b-1-1)

式(b-1-2)

式(b-1-3)

式(b-1-4)

式(b-1-5)

式(b-1-6)The compounds represented by formula (b-1-1) to formula (b-1-6) are shown below:

Formula (b-1-1)

Formula (b-1-2)

Formula (b-1-3)

Formula (b-1-4)

Formula (b-1-5)

Formula (b-1-6)

式(b-2) 式(b-2)中，B¹ 與式(b-1)中的B¹ 相同，B³ 及B⁴ 各自獨立表示二價脂肪族環、二價芳香族環或二價雜環基團； B⁵ 表示碳數為3至18的烷基、碳數為3至18的烷氧基、碳數為1至5的氟烷基、碳數為1至5的氟烷氧基、氰基或鹵素原子。The diamine compound represented by the formula (b-2) is shown below:

Formula (b-2) In formula (b-2), B ¹ is the same as B ¹ in formula (b-1), and B ³ and B ⁴ each independently represent a divalent aliphatic ring, a divalent aromatic ring, or a divalent aromatic ring. Valence heterocyclic group; B ⁵ represents an alkyl group with a carbon number of 3 to 18, an alkoxy group with a carbon number of 3 to 18, a fluoroalkyl group with a carbon number of 1 to 5, and a fluoroalkane with a carbon number of 1 to 5 oxy, cyano or halogen atom.

式(b-2-1)

式(b-2-2)

式(b-2-3)

式(b-2-4)

式(b-2-5)

式(b-2-6)

式(b-2-7)

式(b-2-8)

式(b-2-9)

式(b-2-10)

式(b-2-11)

式(b-2-12)

式(b-2-13) 式(b-2-1)至式(b-2-13)中，s表示3至12的整數。Specific examples of the compound represented by the formula (b-2) include at least one of the compounds represented by the following formulas (b-2-1) to (b-2-13):

Formula (b-2-1)

Formula (b-2-2)

Formula (b-2-3)

Formula (b-2-4)

Formula (b-2-5)

Formula (b-2-6)

Formula (b-2-7)

Formula (b-2-8)

Formula (b-2-9)

Formula (b-2-10)

Formula (b-2-11)

Formula (b-2-12)

Formula (b-2-13) In formula (b-2-1) to formula (b-2-13), s represents an integer of 3 to 12.

式(b-3) 式(b-3)中，B⁶ 各自獨立表示氫原子、碳數為1至5的醯基、碳數為1至5的烷基、碳數為1至5的烷氧基或鹵素原子，且每個重複單元中的B⁶ 可為相同或不同； u表示1至3的整數。The diamine compound represented by the formula (b-3) is shown below:

Formula (b-3) In formula (b-3), B ⁶ each independently represents a hydrogen atom, an acyl group having 1 to 5 carbon atoms, an alkyl group having 1 to 5 carbon atoms, and an alkane having 1 to 5 carbon atoms. an oxy group or a halogen atom, and B ⁶ in each repeating unit may be the same or different; u represents an integer of 1 to 3.

Specific examples of the compound represented by the formula (b-3) include when u is 1: p-diaminebenzene, m-diaminebenzene, o-diaminebenzene or 2,5-diaminotoluene, etc.; when u is When it is 2: 4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diphenyl Aminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 2,2'-dichloro-4,4'-diaminobiphenyl, 3,3'- Dichloro-4,4'-diaminobiphenyl, 2,2',5,5'-tetrachloro-4,4'-diaminobiphenyl, 2,2'-dichloro-4,4' -Diamino-5,5'-dimethoxybiphenyl or 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl, etc.; or when u is 3: 1 , 4-bis(4'-aminophenyl)benzene, etc.

Specific examples of the compound represented by formula (b-3) preferably include p-diaminobenzene, 2,5-diaminotoluene, 4,4'-diaminobiphenyl, 3,3'-dimethylbenzene Oxy-4,4'-diaminobiphenyl, 1,4-bis(4'-aminophenyl)benzene, or a combination of the foregoing.

式(b-4) 式(b-4)中，v表示2至12的整數。The diamine compound represented by the formula (b-4) is shown below:

Formula (b-4) In formula (b-4), v represents an integer of 2 to 12.

式(b-5) 式(b-5)中，w表示1至5的整數。The diamine compound represented by the formula (b-5) is shown below:

Formula (b-5) In formula (b-5), w represents an integer of 1 to 5.

The compound represented by formula (b-5) is preferably 4,4'-diamino-diphenyl sulfide.

式(b-6) 式(b-6)中，B⁷ 及B⁹ 各自獨立表示二價有機基團，且B⁷ 及B⁹ 可為相同或不同； B⁸ 表示衍生自吡啶、嘧啶、三嗪、哌啶或哌嗪等含氮原子的環狀結構的二價基團。The diamine compound represented by the formula (b-6) is shown below:

Formula (b-6) In formula (b-6), B ⁷ and B ⁹ each independently represent a divalent organic group, and B ⁷ and B ⁹ may be the same or different; B ⁸ represents derived from pyridine, pyrimidine, trivalent Divalent groups of cyclic structures containing nitrogen atoms such as oxazine, piperidine or piperazine.

式(b-7) 式(b-7)中，B¹⁰ 、B¹¹ 、B¹² 及B¹³ 各自獨立表示碳數為1至12的烴基，且B¹⁰ 、B¹¹ 、B¹² 及B¹³ 可為相同或不同； x1各自獨立表示1至3的整數；及 x2表示1至20的整數。The diamine compound represented by the formula (b-7) is shown below:

Formula (b-7) In formula (b-7), B ¹⁰ , B ¹¹ , B ¹² and B ¹³ each independently represent a hydrocarbon group having 1 to 12 carbon atoms, and B ¹⁰ , B ¹¹ , B ¹² and B ¹³ may be are the same or different; x1 each independently represents an integer from 1 to 3; and x2 represents an integer from 1 to 20.

式(b-8) 式(b-8)中，B¹⁴ 表示氧原子或伸環己烷基； B¹⁵ 表示亞甲基； B¹⁶ 表示伸苯基或伸環己烷基；及 B¹⁷ 表示氫原子或庚基。The diamine compound represented by the formula (b-8) is shown below:

Formula (b-8) In formula (b-8), B ¹⁴ represents an oxygen atom or a cyclohexylene group; B ¹⁵ represents a methylene group; B ¹⁶ represents a phenylene group or a cyclohexylene group; and B ¹⁷ represents hydrogen atom or heptyl group.

式(b-8-1)

式(b-8-2)Specific examples of the compound represented by the formula (b-8) include the compound represented by the formula (b-8-1), the compound represented by the formula (b-8-2), or a combination of the above compounds:

Formula (b-8-1)

Formula (b-8-2)

式(b-9)

式(b-10)

式(b-11)

式(b-12)

式(b-13)

式(b-14)

式(b-15)

式(b-16)

式(b-17)

式(b-18)

式(b-19)

式(b-20)

式(b-21)

式(b-22)

式(b-23)

式(b-24)

式(b-25) 式(b-17)至式(b-25)中，B¹⁸ 較佳為表示碳數為1至10的烷基或碳數為1至10的烷氧基；B¹⁹ 較佳為表示氫原子、碳數為1至10的烷基或碳數為1至10的烷氧基。The compounds represented by formula (b-9) to formula (b-25) are shown below:

Formula (b-9)

Formula (b-10)

Formula (b-11)

Formula (b-12)

Formula (b-13)

Formula (b-14)

Formula (b-15)

Formula (b-16)

Formula (b-17)

Formula (b-18)

Formula (b-19)

Formula (b-20)

Formula (b-21)

Formula (b-22)

Formula (b-23)

Formula (b-24)

Formula (b-25) In formula (b-17) to formula (b-25), B ¹⁸ preferably represents an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms; B ¹⁹ Preferably, it represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms.

式(b-26) 式(b-26)中，B⁰ 、B² 分別獨立表示單鍵、-O-、-COO-或-OCO-；B¹ 為碳數為1至3的伸烷基；B³ 為單鍵或碳數為1至3的伸烷基。d與g各自獨立表示0或1；e表示0至2的整數；f表示1至20的整數；其中d與e不同時為0。

Formula (b-26) In formula (b-26), B ⁰ and B ² each independently represent a single bond, -O-, -COO- or -OCO-; B ¹ is an alkylene group having 1 to 3 carbon atoms ; B ³ is a single bond or an alkylene group with 1 to 3 carbon atoms. d and g each independently represent 0 or 1; e represents an integer from 0 to 2; f represents an integer from 1 to 20; wherein d and e are not 0 at the same time.

In formula (b-26), the divalent group represented by "-B ⁰ -(B ¹ -B ² ) _g -" is preferably an alkylene group having 1 to 3 carbon atoms, *-O-, * -COO- or *-OC ₂ H ₄ -O- (wherein, * represents a bond with a diaminophenyl group.). The group represented by "-C _f H _2f+1 " is preferably linear. The positions of the two amine groups in the diaminophenyl group are preferably 2, 4 or 3, 5 with respect to other groups.

式(b-26-1)

式(b-26-2)

式(b-26-3)

式(b-26-4)Specific examples of the compound represented by the formula (b-26) include compounds represented by the following formulae (b-26-1) to (b-26-4):

Formula (b-26-1)

Formula (b-26-2)

Formula (b-26-3)

Formula (b-26-4)

The diamine component (b) can be used alone or in combination.

Specific examples of the diamine component (b) preferably include, but are not limited to, 1,2-diaminoethane, 4,4'-diaminodicyclohexylmethane, 4,4'-diaminodicyclohexane Phenylmethane, 4,4'-diaminodiphenyl ether, 5-[4-(4-n-pentylcyclohexyl)cyclohexyl]phenylmethylene-1,3-diaminobenzene, 1,1-Bis[4-(4-aminophenoxy)phenyl]-4-(4-ethylphenyl)cyclohexane, 2,4-diaminophenylcarboxylate, 1- Octadecyloxy-2,4-diaminobenzene, compound represented by formula (b-1-1), compound represented by formula (b-1-2), compound represented by formula (b-2-1) The compound represented by the formula (b-2-11), p-diaminebenzene, m-diaminebenzene, o-diaminebenzene, the compound represented by the formula (b-8-1), or the above combination of compounds.

The polymer (A) may include at least one of polyamic acid and polyimide. In addition, the polymer (A) may further include a polyimide-based block copolymer. The preparation methods of the above-mentioned various polymer compositions are further described below.

The method for preparing polyamic acid is to first dissolve the mixture in a solvent, wherein the mixture includes a tetracarboxylic dianhydride component (a) and a diamine component (b), and the mixture is heated at a temperature of 0 ° C to 100 ° C. A polycondensation reaction is carried out. After 1 hour to 24 hours of reaction, the reaction solution is distilled under reduced pressure with an evaporator to obtain polyamic acid. Alternatively, the reaction solution is poured into a large amount of lean solvent to obtain a precipitate. Next, the precipitate is dried under reduced pressure to obtain a polyamide acid.

Based on 100 mol of the diamine component (b), the used amount of the tetracarboxylic dianhydride component (a) is 20 mol to 200 mol; more preferably, the tetracarboxylic dianhydride Component (a) is used in an amount of 30 mol to 120 mol.

The solvent used in the polycondensation reaction may be the same as or different from the solvent used in the liquid crystal aligning agent described below, and the solvent used in the polycondensation reaction is not particularly limited as long as it can dissolve the reactant and the product. The solvent preferably includes but is not limited to (1) aprotic polar solvents, such as: N-methyl-2-pyrrolidinone (N-methyl-2-pyrrolidinone; NMP), N,N-dimethylacetamide, Aprotic polar solvents such as N,N-dimethylformamide, dimethylsulfoxide, γ-butyrolactone, tetramethylurea or hexamethylphosphoric triamine; or (2) phenolic solvents, For example, phenolic solvents such as m-cresol, xylenol, phenol, and halogenated phenols. The solvent used in the polycondensation reaction is preferably used in an amount of 200 to 2000 parts by weight, and more preferably 300 to 1800 parts by weight, based on 100 parts by weight of the total mixture.

It is worth noting that in the polycondensation reaction, the solvent can be used in combination with an appropriate amount of poor solvent, wherein the poor solvent will not cause the precipitation of polyamide acid. The poor solvent can be used alone or in combination, and it includes but is not limited to (1) alcohols, such as methanol, ethanol, isopropanol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butanediol Alcohols such as alcohol or triethylene glycol; (2) ketones, such as: ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.; (3) esters, such as: Esters of methyl acetate, ethyl acetate, butyl acetate, diethyl oxalate, diethyl malonate or ethylene glycol ethyl ether acetate; (4) ethers, such as diethyl ether, Ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol n-propyl ether, ethylene glycol isopropyl ether, ethylene glycol n-butyl ether, ethylene glycol dimethyl ether or diethylene glycol dimethyl ether ethers such as base ethers; (5) halogenated hydrocarbons, such as dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene or o-dichloromethane Halogenated hydrocarbons such as benzene; or (6) hydrocarbons, for example: hydrocarbons such as tetrahydrofuran, hexane, heptane, octane, benzene, toluene or xylene, or any combination of the above solvents. The amount of the lean solvent used is preferably 0 to 60 parts by weight, and more preferably 0 to 50 parts by weight, based on 100 parts by weight of the diamine component (b).

The method for preparing polyimide is obtained by heating the polyamic acid prepared by the above-mentioned method for preparing polyamic acid in the presence of a dehydrating agent and a catalyst. During the heating process, the aramidic acid functional group in the polyamic acid can be converted into an imidimine functional group via a dehydration ring-closure reaction (ie, imidization).

The solvent used in the dehydration ring-closing reaction can be the same as the solvent (B) in the liquid crystal alignment agent, so it is not repeated here. The amount of the base polyamide used is 100 parts by weight, and the amount of the solvent used in the dehydration ring-closure reaction is preferably 200 to 2000 parts by weight, and more preferably 300 to 1800 parts by weight.

In order to obtain a better degree of imidization of the polyamic acid, the operating temperature of the dehydration ring-closure reaction is preferably 40°C to 200°C, more preferably 40°C to 150°C. If the operating temperature of the dehydration ring-closure reaction is lower than 40° C., the imidization reaction is not complete, and the degree of imidization of the polyamic acid is reduced. However, if the operating temperature of the dehydration ring-closure reaction is higher than 200°C, the weight-average molecular weight of the obtained polyimide is low.

The dehydrating agent used in the dehydration ring-closure reaction can be selected from acid anhydride compounds, such as acid anhydride compounds such as acetic anhydride, propionic anhydride or trifluoroacetic anhydride. The amount of the dehydrating agent used is 0.01 mol to 20 mol based on 1 mol of the polyamide. The catalyst used in the dehydration ring-closure reaction can be selected from (1) pyridine compounds, such as: pyridine compounds such as pyridine, collidine or lutidine; (2) tertiary amine compounds, such as: Tertiary amine compounds such as triethylamine. Based on 1 mol of the dehydrating agent, the used amount of the catalyst may be 0.5 mol to 10 mol.

In a specific example of the present invention, the imidization rate of the polymer composition (A) is 30% to 90%, preferably 35% to 85%, more preferably 40% to 80%. When the imidization ratio of the polymer composition (A) is within the above-mentioned range, the obtained liquid crystal aligning agent has better ink jet printing coatability.

The polyimide block copolymer is selected from the group consisting of polyimide block copolymer, polyimide block copolymer, polyimide-polyimide block copolymer or the above-mentioned polymerization any combination of things.

The method for preparing the polyimide-based block copolymer is preferably to first dissolve the starting material in a solvent and carry out a polycondensation reaction, wherein the starting material includes at least one polyamide acid and/or at least one polyamide imine, and may further include a tetracarboxylic dianhydride component (a) and a diamine component (b).

The tetracarboxylic dianhydride component and the diamine component in the starting material can be the same as the tetracarboxylic dianhydride component (a) and the diamine component (b) used in the method for preparing polyamic acid, And the solvent used in the polycondensation reaction can be the same as the solvent (B) in the following liquid crystal alignment agent, which is not repeated here.

The solvent used in the polycondensation reaction is preferably used in an amount of 200 to 2000 parts by weight, and more preferably 300 to 1800 parts by weight, based on 100 parts by weight of the starting material. The operating temperature of the polycondensation reaction is preferably 0°C to 200°C, and more preferably 0°C to 100°C.

The starting materials preferably include but are not limited to (1) two kinds of polyamides with different end groups and different structures; (2) two kinds of polyimides with different end groups and different structures; (3) ) Polyamic acid and polyimide with different end groups and different structures; (4) Polyamic acid, tetracarboxylic dianhydride component and diamine component, among which, tetracarboxylic dianhydride component At least one of the diamine components is different in structure from the tetracarboxylic dianhydride component and the diamine component used to form the polyamide acid; (5) polyimide, tetracarboxylic dianhydride group component and diamine component, wherein, at least one of the tetracarboxylic dianhydride component and the diamine component is structurally different from the tetracarboxylic dianhydride component and the diamine component used to form the polyimide (6) polyamide acid, polyimide, tetracarboxylic dianhydride component and diamine component, wherein, at least one of the tetracarboxylic dianhydride component and the diamine component is combined with the formation of polyamide The tetracarboxylic dianhydride component and the diamine component used in the acid or polyimide have different structures; (7) two kinds of polyamide acid, tetracarboxylic dianhydride component and diamine with different structures components; (8) two kinds of polyimide, tetracarboxylic dianhydride component and diamine component with different structures; (9) two kinds of polyamide acids whose end groups are acid anhydride groups and different structures and Diamine component; (10) Two kinds of polyamide acid and tetracarboxylic dianhydride components whose end groups are amine groups and different structures; (11) Two kinds of polyamides whose end groups are acid anhydride groups and different structures imine and diamine components; or (12) two kinds of polyimide and tetracarboxylic dianhydride components whose terminal groups are amine groups and have different structures.

In the range that does not affect the efficacy of the present invention, polyimide, polyimide and polyimide-based block copolymers are preferably terminal-modified polymers whose molecular weights are adjusted first. By using the terminal-modified polymer, the coating performance of the liquid crystal alignment agent can be improved. The method of preparing the terminal-modified polymer can be prepared by adding a monofunctional compound at the same time as the polyamide acid undergoes a polycondensation reaction.

Specific examples of monofunctional compounds include, but are not limited to (1) monobasic acid anhydrides such as maleic anhydride, phthalic anhydride, itaconic anhydride, n-decylsuccinic anhydride, n-dodecylsuccinic anhydride, n-tetradecylsuccinic anhydride Monobasic acid anhydrides such as alkyl succinic anhydride or n-hexadecyl succinic anhydride; (2) monoamine compounds, such as: aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, n-undecylamine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecylamine, Monoamine compounds such as n-octadecylamine or n-eicosylamine; or (3) monoisocyanate compounds, for example: monoisocyanate compounds such as phenyl isocyanate or naphthyl isocyanate.

The polymer (A) of the present invention has a polystyrene-converted weight-average molecular weight of 2,000 to 200,000, preferably 3,000 to 100,000, as measured by Gel Permeation Chromatography (GPC). 4000 to 50000.

式(1) 式(1)中，R₁ 為C₂ 至C₁₂ 之烷基。The solvent (B) of the present invention contains the compound (B-1) represented by the formula (1), 4,6-dimethyl-2-heptanone (B-2) and 2,6-dimethyl-4- Heptanone (B-3);

Formula (1) In formula (1), R ₁ is a C ₂ to C ₁₂ alkyl group.

In the compound (B-1) represented by the formula (1), R ₁ is an alkyl group of C ₂ to C ₁₂ , such as ethyl, isopropyl, neobutyl, isobutyl and the like. That is, the compound (B-1) represented by the formula (1) can be N-ethyl-2-pyrrolidone, N-isopropyl-2-pyrrolidone, N-neobutyl-2-pyrrolidone, N-isopropyl-2-pyrrolidone Butyl-2-pyrrolidone, etc.

Based on the content of the solvent (B) being 100% by weight, the content of the compound (B-1) represented by the formula (1) is usually 30% by weight to 80% by weight; preferably 35% by weight to 75% by weight; More preferably, it is 40% by weight to 70% by weight.

In addition, the content of the 4,6-dimethyl-2-heptanone (B-2) is usually 0.01 to 10% by weight based on 100% by weight of the solvent (B); preferably 0.05% by weight % to 10% by weight; more preferably 0.05% to 8% by weight.

Furthermore, the content of the 2,6-dimethyl-4-heptanone (B-3) is usually 1 to 20% by weight based on 100% by weight of the solvent (B); preferably 3 % to 20% by weight; more preferably 5% to 20% by weight.

If the solvent (B) does not use the compound (B-1) represented by the formula (1), 4,6-dimethyl-2-heptanone (B-2) and 2,6-dimethyl-4- If heptanone (B-3) is used, the obtained liquid crystal alignment agent has poor inkjet printing coating properties.

Preferably, the solvent (B) of the present invention may further comprise an alcohol or glycol compound (B-4), and the alcohol or glycol compound (B-4) is selected from ethoxyethanol, butoxy The group consisting of ethylene glycol, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether or diethylene glycol.

Based on 100% by weight of the solvent (B), the content of the alcohol or glycol compound (B-4) is usually 15% to 60% by weight; preferably 20% to 60% by weight; more It is preferably 25% by weight to 60% by weight.

If the solvent (B) contains the alcohol or diol compound (B-4), and the content thereof falls within the above range, the obtained liquid crystal alignment agent has better inkjet printing coatability.

式(2) 式(2)中，n為1或2，且R¹ 、R² 為C₁ 至C₄ 之烷基。Preferably, the solvent (B) of the present invention may further comprise the compound (B-5) represented by the formula (2):

Formula (2) In formula (2), n is 1 or 2, and R ¹ and R ² are C ₁ to C ₄ alkyl groups.

The compound (B-5) represented by the formula (2) can be diethylene glycol ethyl methyl ether, diethylene glycol diethyl ether, diethylene glycol isopropyl methyl ether, diethylene glycol butyl methyl ether, ethylene glycol Glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dipropyl ether, ethylene glycol dibutyl ether, and the like can be used alone or in combination.

Based on the content of the solvent (B) being 100% by weight, the content of the compound (B-5) represented by the formula (2) is usually 1% by weight to 20% by weight; preferably 3% by weight to 20% by weight; More preferably, it is 5% by weight to 20% by weight.

If the solvent (B) contains the compound (B-5) represented by the formula (2), and its content falls within the above-mentioned range, the obtained liquid crystal alignment agent has better inkjet printing coatability.

The solvent (B) of the present invention may further comprise other solvents (B-6), such as N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl caprolactone, dimethyl sulfoxide, tetramethyl urea, hexamethyl phosphamide, γ-butyrolactone, etc.; also can be used in combination with methanol, ethanol, isopropanol, n-butanol, cyclic Hexanol, diethyl ether, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, ethyl acetate, tetrahydrofuran, dichloromethane, chloroform, 1,2-dichloroethane, benzene, toluene , xylene, n-hexane, n-heptane, n-octane, etc. < The manufacturing method of liquid crystal aligning agent >

The manufacturing method of the liquid crystal aligning agent is not particularly limited, and it can be prepared by a general mixing method. For example, the tetracarboxylic dianhydride component (a) and the diamine component (b) are mixed uniformly to react to form a polymer (A). Next, the polymer (A) is added to the solvent (B) at a temperature of 0 ° C to 200 ° C, and the additive (C) can be optionally added, and the stirring device is continuously stirred until dissolved. Preferably, the solvent (B) is added to the polymer composition at a temperature of 20°C to 60°C.

Preferably, at 25°C, the viscosity of the liquid crystal alignment agent of the present invention is usually 15 cps to 35 cps, preferably 17 cps to 33 cps, more preferably 20 cps to 30 cps. <Manufacturing method of liquid crystal alignment film>

The liquid crystal alignment film of the present invention can be formed from the above-mentioned liquid crystal alignment agent.

Specifically, the preparation method of the liquid crystal alignment film can be, for example, coating the liquid crystal alignment agent on the surface of the substrate by a roll coating method, a spin coating method, a printing method or an ink-jet method. , to form a precoat, preferably an inkjet method. Next, the pre-coat layer is subjected to pre-bake treatment, post-bake treatment, and alignment treatment to prepare a substrate with a liquid crystal alignment film formed thereon.

Preferably, the manufacturing method of the liquid crystal alignment film of the present invention is to form a liquid crystal alignment film from the aforementioned liquid crystal alignment agent by an inkjet printing method.

The purpose of the prebake treatment is to volatilize the organic solvent in the precoat. The operating temperature of the prebaking treatment is preferably 30°C to 120°C, more preferably 40°C to 110°C, and particularly preferably 50°C to 100°C.

The alignment treatment is not particularly limited, and a fabric made of fibers such as nylon, rayon, or cotton can be wound around a drum and rubbed in a certain direction for alignment.

The purpose of the post-bake treatment step is to subject the polymer in the precoat to a further dehydration ring closure (imidization) reaction. The operating temperature of the post-baking treatment is preferably 150°C to 300°C, more preferably 180°C to 280°C, particularly preferably 200°C to 250°C. < Liquid crystal display element and its manufacturing method >

The liquid crystal display element of the present invention includes a liquid crystal alignment film formed of the liquid crystal alignment agent of the present invention. The manufacturing method of a liquid crystal display element is well known to those skilled in the art. Therefore, the following statements are made only briefly.

FIG. 1 is a side view of a liquid crystal display element according to an embodiment of the present invention. The liquid crystal display element 100 includes a first cell 110 , a second cell 120 and a liquid crystal cell 130 , wherein the second cell 120 is disposed separately from the first cell 110 , and the liquid crystal cell 130 is disposed between the first cell 110 and the second cell 120 .

The first unit 110 includes a first substrate 112 , a first conductive film 114 and a first liquid crystal alignment film 116 , wherein the first conductive film 114 is formed on the surface of the first substrate 112 . In addition, the first conductive film 114 is located between the first substrate 112 and the first liquid crystal alignment film 116 , and the first liquid crystal alignment film 116 is located on one side of the liquid crystal cell 130 .

The second unit 120 includes a second substrate 122 , a second conductive film 124 and a second liquid crystal alignment film 126 , wherein the second conductive film 124 is formed on the surface of the second substrate 122 . In addition, the second conductive film 124 is located between the second substrate 122 and the second liquid crystal alignment film 126 , and the second liquid crystal alignment film 126 is located on the other side of the liquid crystal cell 130 . In other words, the liquid crystal cell 130 is located between the first liquid crystal alignment film 116 and the second liquid crystal alignment film 126 .

The first substrate 112 and the second substrate 122 are selected from transparent materials, etc., wherein the transparent materials include but are not limited to alkali-free glass, soda lime glass, hard glass (Pyles glass), quartz glass for liquid crystal display devices , polyethylene terephthalate, polybutylene terephthalate, polyether terephthalate or polycarbonate, etc.

The materials of the first conductive film 114 and the second conductive film 124 are selected from tin oxide (SnO ₂ ), indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ), and the like.

The first liquid crystal alignment film 116 and the second liquid crystal alignment film 126 are respectively the above-mentioned liquid crystal alignment films, and their functions are to form a pretilt angle of the liquid crystal cell 130 . In addition, when a voltage is applied to the first conductive film 114 and the second conductive film 124, an electric field may be generated between the first conductive film 114 and the second conductive film 124. The electric field can drive the liquid crystal cell 130 , thereby changing the arrangement of liquid crystal molecules in the liquid crystal cell 130 .

The liquid crystals used in the liquid crystal cell 130 can be used alone or in combination, and the liquid crystals include, but are not limited to, diaminobenzene-based liquid crystals, pyridazine-based liquid crystals, Schiff Base-based liquid crystals, azo-based liquid crystals ( azoxy) liquid crystal, biphenyl (biphenyl) liquid crystal, phenylcyclohexane (phenylcyclohexane) liquid crystal, ester (ester) liquid crystal, terphenyl (terphenyl), biphenylcyclohexane (biphenylcyclohexane) liquid crystal, pyrimidine ( pyrimidine) liquid crystals, dioxane liquid crystals, bicyclooctane liquid crystals or cubane liquid crystals, etc., and for example, cholesteryl chloride, cholesteryl chloride can be added as needed. Cholesteryl liquid crystals such as cholesteryl nonanoate and cholesteryl carbonate, or chiral agents under the trade names "C-15" and "CB-15" (manufactured by Merck), etc. , or a ferroelectric liquid crystal such as p-decyloxybenzylidene-p-amino-2-methylbutyl cinnamate.

The following examples are used to illustrate the present invention in detail, but it is not intended that the present invention is limited to the contents disclosed by these examples. [ Preparation of Polymer (A) ] < Synthesis Example A-1-1>

A nitrogen inlet, a stirrer, a condenser and a thermometer were set on a four-necked conical flask with a volume of 500 ml, and nitrogen was introduced. Then, in a four-necked conical flask, add 0.035 mol of p-diamine benzene (abbreviated as b-1), 0.015 mol of b-4 shown in Table 1 and 80 grams of N-methyl-2- Pyrrolidone (N-methyl-2-pyrrolidone, referred to as NMP), and stirred at room temperature until dissolved. Next, 0.05 mol of 2,3,5-tricarboxycyclopentylacetic dianhydride (abbreviated as a-1) and 20 g of NMP were added, and the mixture was reacted at room temperature for 2 hours. After the reaction was completed, the reaction solution was poured into 1500 ml of water to precipitate the polymer. Then, the obtained polymer was filtered, washed with methanol and filtered three times repeatedly, placed in a vacuum oven, and dried at a temperature of 60° C. to obtain the polymer (A-1-1). < Synthesis Examples A-1-2 and A-1-3>

Synthesis Examples A-1-2 and A-1-3 are prepared by the same procedure as Synthesis Example A-1-1, except that the tetracarboxylic dianhydride component or the diamine component is changed. The types and amounts used are shown in Table 1. < Synthesis example A-2-1>

A nitrogen inlet, a stirrer, a condenser and a thermometer were set on a four-necked conical flask with a volume of 500 ml, and nitrogen was introduced. Then, in a four-necked conical flask, add 0.04 mol of 4,4'-diaminodiphenylmethane (abbreviated as b-2), 0.01 mol of b-4 shown in Table 1 and 80 g of N-methyl-2-pyrrolidone (N-methyl-2-pyrrolidone, abbreviated as NMP), and stirred at room temperature until dissolved. Next, 0.05 moles of 2,3,5-tricarboxycyclopentylacetic dianhydride (abbreviated as a-1) and 20 grams of NMP were added. After reacting at room temperature for 6 hours, 97 g of NMP, 0.01 mol of acetic anhydride and 0.02 mol of pyridine were added, the temperature was raised to 120°C, and stirring was continued for 2 hours to carry out imidization reaction. After the reaction was completed, the reaction solution was poured into 1500 ml of water to precipitate the polymer. Then, the obtained polymer was filtered, washed with methanol and filtered three times, placed in a vacuum oven, and dried at a temperature of 60° C. to obtain the polymer (A-2-1). < Synthesis Examples A-2-2 to A-2-10>

表1中：

[ 液晶配向劑、液晶配向膜及液晶顯示元件之製備 ] ＜ 實施例 1＞ Synthesis Examples A-2-2 to A-2-10 are prepared by the same procedure as Synthesis Example A-2-1, except that the components of tetracarboxylic dianhydride and diamine are changed. The type and usage amount, as well as the usage amount and reaction temperature of the catalyst for changing the dehydrating agent and dehydration ring-closure reaction, are shown in Table 1. Table 1:

in FIG. 1:

[ Preparation of Liquid Crystal Alignment Agent, Liquid Crystal Alignment Film, and Liquid Crystal Display Device ] < Example 1>

100 parts by weight of polymer (A-1-1), 79 parts by weight of N-ethyl-2-pyrrolidone (abbreviated as B-1-1), 1 part by weight of 4,6-dimethyl- 2-heptanone (B-2) and 20 parts by weight of 2,6-dimethyl-4-heptanone (B-3) were stirred and mixed at room temperature to form the liquid crystal aligning agent of Example 1.

The liquid crystal aligning agent was evaluated for each test item, and the results obtained are shown in Table 3. < Examples 2 to 15 and Comparative Examples 1 to 3>

表2-2：

表3：

表2-1、表2-2及表3中：

[ 檢測項目 ] ＜ 醯亞胺化率 ＞ Examples 2 to 15 and Comparative Examples 1 to 3 are the same steps as in Example 1 to prepare the liquid crystal alignment agent, except that the types of polymer compositions, solvents and additives and their usage amounts are changed, as shown in the table 2-1, Table 2-2 and Table 3. These liquid crystal aligning agents were evaluated for each test item, and the results obtained are shown in Table 2-1, Table 2-2 and Table 3. table 2-1:

Table 2-2:

table 3:

In Table 2-1, Table 2-2 and Table 3:

[ Test item ] < Imidization rate >

The imidization rate refers to the ratio of the number of imide rings to be calculated based on the total amount of the number of imide functional groups and the number of imine rings in the polyimide polymer, and Expressed as a percentage.

The method for detecting the imidization rate is to dry the polymers (A) in the above-mentioned synthesis examples A-1-1 to A-2-10 under reduced pressure, and then dissolve the above-mentioned polymers (A) in a suitable In a deuterated solvent (such as deuterated dimethyl sulfoxide), and using tetramethylsilane as a reference material, the ¹ H-NMR (hydrogen nuclear magnetic resonance) was measured at room temperature (such as 25°C). As a result, the imidization rate (%) of the polymer (A) was calculated by the following formula:

In the formula, Δ1 represents the peak area generated by the chemical shift of the NH proton around 10 ppm, Δ2 represents the peak area of other protons, and α represents the polymerization in the polymer composition (A) The ratio of the number of one proton of the NH group relative to the other protons in the polyamide precursor of the product. < Inkjet Printing Coatability >

The glass substrate with the transparent electrode made of ITO was heated on a hot plate at 200°C for one minute, and then cleaned with ultraviolet/ozone, so that the contact angle of water droplets on the surface of the transparent electrode was less than 10°, as a follow-up coating. Liquid crystal alignment agent substrate.

The liquid crystal aligning agents of the aforementioned Examples 1 to 15 and Comparative Examples 1 to 3 were taken and coated on the surface of the transparent electrode on the surface of the glass substrate using an ink jet coater (manufactured by Shibaura Mechatronics). The coating conditions were 2,500 times/(nozzle•min), and the coating amount was 250 mg/10 seconds, and two round trips were performed (4 times in total). After finishing the coating, let it stand for 1 minute, and continue heating to form a coating film with a thickness of 0.1 μm. After the above coating film was obtained, it was irradiated with an interference fringe measuring lamp (sodium lamp) and observed with the naked eye to evaluate the degree of unevenness and cissing. The heating temperatures were 50°C, 60°C, and 80°C, respectively, and the evaluation criteria were as follows: ◎: excellent, no unevenness and shrinkage at the above three temperatures; ○: good, unevenness at one of the temperatures and/or shrinkage; △: OK, unevenness and/or shrinkage at two of the temperatures; and ╳: Bad, unevenness and/or shrinkage at all three temperatures.

The above-mentioned embodiments are only to illustrate the principle and effect of the present invention, but not to limit the present invention. Modifications and changes made to the above embodiments by those skilled in the art still do not violate the spirit of the present invention. The scope of the rights of the present invention should be listed in the scope of the patent application described later.

100‧‧‧LCD element 110‧‧‧First unit 112‧‧‧First substrate 114‧‧‧First conductive film 116‧‧‧First liquid crystal alignment film 120‧‧‧Second unit 122‧‧‧First Two substrates 124‧‧‧Second conductive film 126‧‧‧Second liquid crystal alignment film 130‧‧‧Liquid crystal cell

FIG. 1 is a side view of a liquid crystal display element according to an embodiment of the present invention.

100‧‧‧LCD components

110‧‧‧Unit 1

112‧‧‧First substrate

114‧‧‧First Conductive Film

116‧‧‧First liquid crystal alignment film

120‧‧‧Unit 2

122‧‧‧Second board

124‧‧‧Second Conductive Film

126‧‧‧Second liquid crystal alignment film

130‧‧‧LCD unit

Claims (9)

A liquid crystal alignment agent, comprising: a polymer (A), prepared by reacting a mixture comprising a tetracarboxylic dianhydride component (a) and a diamine component (b); and a solvent (B), comprising the formula ( 1) Compound (B-1), 4,6-dimethyl-2-heptanone (B-2) and 2,6-dimethyl-4-heptanone (B-3) shown in 1);

In the formula (1), R ₁ is an alkyl group of C ₂ to C ₁₂ ; wherein the content of the compound (B-1) represented by the formula (1) is 30% by weight based on the content of the solvent (B) of 100% by weight. % by weight to 80% by weight; the content of the 4,6-dimethyl-2-heptanone (B-2) is 0.01% by weight to 10% by weight; and the 2,6-dimethyl-4-heptanone The content of (B-3) is 1% by weight to 20% by weight. The liquid crystal aligning agent according to claim 1, wherein the solvent (B) further comprises an alcohol or diol compound (B-4), the alcohol or diol compound (B-4) is selected from Ethoxyethanol, butoxyethanol, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether or diethylene glycol formed group. The liquid crystal alignment agent according to claim 2, wherein the content of the alcohol or diol compound (B-4) is 15 to 60 wt % based on 100 wt % of the solvent (B) . The liquid crystal aligning agent according to claim 1, wherein the solvent (B) further comprises a compound (B-5) represented by formula (2): R ¹ -O(CH ₂ CH ₂ O)nR ² formula ( 2) In formula (2), n is 1 or 2, and R ¹ and R ² are C ₁ to C ₄ alkyl groups. The liquid crystal alignment agent according to claim 4, wherein the content of the compound (B-5) represented by the formula (2) is 1 to 20 wt % based on 100 wt % of the solvent (B) %. The liquid crystal aligning agent according to claim 1, wherein the imidization rate of the polymer (A) is 30% to 90%. A liquid crystal alignment film is formed from the liquid crystal alignment agent according to any one of claims 1 to 6. A liquid crystal display element comprising the liquid crystal alignment film according to claim 7. A method for manufacturing a liquid crystal alignment film is to form a liquid crystal alignment film from the liquid crystal alignment agent described in any one of claims 1 to 6 by an inkjet printing method.

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